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Authors
Sette Diop

Identifier
10.3182/20060329-3-AU-2901.00131

Index Terms
observability,identifiability,parameter estimation,nonlinear control systems,algebraic systems theory

Abstract
In this Communication we show that for any dynamics given by a rational state vector equation dx/dt = f(u,x) there always is a scalar linear observation y = α1x1 + α2x2 + ... + αnxn which makes the state x observable provided that the coefficients α1, α2, ... , αn are allowed to be nonconstants. Moreover, any such scalar observation makes the system observable if, and only if, the coefficients are linearly independent over constants in a difierential algebraic sense.

References

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